Abstract
Purpose :
Short-term intraocular pressure (IOP) spikes are common after intravitreal injection (IVI). Many approaches have been developed to mitigate these pressure spikes, such as different needle sizes or IOP lowering medications. We hypothesize that anterior chamber decompression with the sterile caliper used to mark the injection site reduces the IOP spike.
Methods :
This was an IRB-approved retrospective interventional comparative case series at the Iowa City VA Medical Center from July to August 2022. IOP of the injection eye was obtained (Tonopen, Reichert, Depew, NY) both before (baseline) and within 30s after IVI. Subjects were randomly assigned to a control arm, where the disposable caliper (Moria Instruments, Paris, France) was applied to mark the injection site for <1s and no extra pressure was exerted, or intervention arm, where the caliper was applied for approximately 10s with sustained pressure on the limbus. Otherwise, IVI procedure followed standard-of-care under sterile conditions for both arms. Baseline and post-injection IOP (mmHg, SD) were compared between groups using student’s t-test.
Results :
Thirty-two eyes from 31 patients were included. The average age was 74.5 at the time of injection. Patients underwent standardized injections with 0.05 ml bevacizumab (14/32), 0.05 ml aflibercept (15/32), or 0.05 ml ranibizumab (2/32). In the 17/32 eyes in the control arm, baseline IOP was 16.35 mmHg (3.06) and post-injection IOP was 43.88 mmHg (10.37), with an average delta IOP of 27.53 mmHg (11.66). In the 15/32 eyes in the intervention arm, baseline IOP was 15.47 mmHg (3.29) and post-injection IOP was 24.73 mmHg (5.23), with average delta of 8.73 mmHg (7.37). There was no significant difference in baseline IOP between groups (p = 0.13), but post-injection IOP was significantly lower in the intervention group than in the control group (p <0.001). No adverse events were noted and compression was tolerated well by patients.
Conclusions :
Sterile caliper ocular decompression prior to routine IVI resulted in significantly decreased IOP compared to patients that did not have decompression. The use of the caliper for ocular decompression saves resources and reduces waste compared to other methods, such as cotton swabs or Q-tips that add procedural waste. It may also lead to fewer complications and interventions due to pressure spikes such as arterial occlusion and permanent visual loss.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.